That's the outlook a day after the Green Bay Packers lost their second straight road game and fell to 3-4-1 at the halfway point of their season.

Allison did not play in Sunday's 31-17 loss to the New England Patriots after he suffered a groin injury in practice Thursday. The third-year receiver was in Philadelphia on Monday to visit Dr. William Meyers, a core-muscle specialist who has operated on Packers players with groin and sports hernia injuries in the past.

"We'll work through the final prognosis, but it's a pretty big injury," coach Mike McCarthy said.

Allison could miss more than a month. Rookie Marquez Valdes-Scantling took Allison's spot as the No. 3 receiver on Sunday and caught three passes for 101 yards -- his second 100-yard game in his past three outings.

King's hamstring injury, which forced him out in the middle of Sunday's game, isn't as big, but McCarthy said King would be "challenged to play this week."

Geronimo Allison will be sidelined after suffering a groin injury. AP

The Packers made several adjustments in the secondary against the Patriots. They started the game with cornerback Tramon Williams at safety in place of Ha Ha Clinton-Dix, who was traded to the Washington Redskins last week. Bashaud Breeland started at cornerback in his first game action since the Packers signed him in December. King started at the other corner spot, and rookie Jaire Alexander played in the slot. Fellow rookie Josh Jackson played 41 of the 71 defensive snaps, most of them after King dropped out 24 snaps into the game. The Packers also finished the game without safety Kentrell Brice, who left with a knee injury.

The Packers on Monday added a safety, former fourth-round pick Ibraheim Campbell, off waivers from the Jets. Campbell played for Packers defensive coordinator Mike Pettine during the 2015 season with the Cleveland Browns.

He took punter Drew Kaser's roster spot. Kaser was signed on Saturday as an emergency in case JK Scott's wife went into labor and he had to leave New England. He would have done so with the blessings of McCarthy and general manager Brian Gutekunst, who had a plane waiting to take Scott back to Green Bay if needed. Kaser instead was inactive.

Right tackle Bryan Bulaga (knee) and linebacker Blake Martinez (ankle) both have a chance to play against the Dolphins after getting injured against the Patriots. Bulaga didn't finish the game but avoided a serious injury, while Martinez returned but had significant swelling on Monday. Martinez said tests showed no significant structural damage.

"Once I taped it up and did a bunch of stuff and tried to run around, it started to kind of loosen up and I was getting ready to go," he said.